Taller trees begin to grow in the last stage
Hormones is the term you are looking for, but I may be wrong
All that is needed is a warmer, lighter fluid below a cooler, heavier one.
Since warm water is lighter, it will rise, and will cool from the top will flow down to replace it, this makes it go in motion
It is poisonous on it's back and is a big species of frogs but not any bigger than a curled up dog.
A plant begin to produce its own food in the following cases:
-when the first leaves are formed
-as soon as photosynthesis starts
Even the little new seeds grown-up from the food reserves, but start making their owm food as they see sunlight